JP2014032034A - Apparatus and method for recovering fine particles containing radioactive metallic substance in muddy water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently separate and recover fine particles containing a radioactive metallic substance from contaminated muddy water without using an adsorbent or a coagulant, and to reduce the amount of radioactive waste.SOLUTION: An apparatus for recovering fine particles containing a radioactive metallic substance in muddy water includes: an air bubble contact tube 42 for causing water to be treated to contact with fine air bubbles; a flock aggregation tube 32 formed in a reverse funnel shape and for causing the fine particles containing the radioactive metallic substance, which floats after being attached to the fine air bubbles, to aggregate as flocks; a flock recovery tube 22 for recovering the aggregated flocks; a foam recovery tube 12 for recovering the fine particles containing the radioactive metallic substance, which floats after being attached to the fine air bubbles, by using foam; and a sedimentation tube 52 formed in a funnel shape and for causing large particles contained in the water to be treated to sediment as sediments and recovering the same from the bottom part thereof. The following processes are performed simultaneously in a single tank, which are: the recovery of the fine particles containing the radioactive metallic substance by using the foam; the recovery of the fine particles containing the radioactive metallic substance by using the flocks; and the recovery of the large particles containing almost none radioactive metallic substance and the treated water.

Description

  The present invention relates to an apparatus and a method for recovering fine particles containing a radioactive metal material diffused in a wide area in a surrounding area such as a field due to an accident at a nuclear power plant or the like.

The Tohoku-Pacific Ocean Earthquake that occurred on March 11, 2011 and the accompanying tsunami caused a long-term loss of all power at the TEPCO Fukushima Daiichi Power Station, resulting in the reactor building. Caused a hydrogen explosion, and a large amount of radioactive material was scattered in the vicinity of Fukushima Prefecture.
Among the scattered radioactive materials, especially radioactive cesium has a long half-life of 30.1 years. Therefore, soil contamination continues for many years, and it is not possible to produce crops for a long time in fields. Damage has occurred.

Currently, various efforts are being made to re-use field soil contaminated with radioactive cesium.
However, fine radioactive metal particles such as radioactive cesium scattered in the field are strongly bound to the fine particles in the soil, and it is difficult to separate only radioactive cesium from the soil. There is a need for a method for efficiently collecting fine particles to which radioactive cesium is attached.
For this reason, rice husk etc. with good adsorptivity to the soil particles are used, the soil particles are adsorbed in the field contaminated with radioactive cesium, and the rice husk etc. adsorbed with the soil particles are washed and washed and the radioactive cesium adheres Attempts have been made to recover soil particles.
At this time, washing water obtained by washing and washing rice husks becomes turbid water due to soil particles containing radioactive metal substances such as radioactive cesium, but if fine particles containing radioactive metal substances can be separated and recovered from this turbid water, Large-diameter soil particles and treated water that are not contaminated by cesium can be reused, and the decontamination work of the contaminated soil can proceed efficiently.

As a conventional method for separating and recovering radioactive cesium from contaminated water contaminated with radioactive cesium, decontamination is performed using an adsorbent such as zeolite or Prussian blue that adsorbs radioactive cesium. There is a way.
However, the use of such an adsorbent in the decontamination work for separating and recovering radioactive cesium, which is estimated to require several decades, will generate a huge amount of high-concentration radioactive waste. In addition, as described above, radioactive cesium is mixed and mixed with fine soil particles, so the adsorbent adsorbs soil particles before adsorbing radioactive cesium, and the adsorption efficiency of the target radioactive substance is significantly reduced. Therefore, it is not considered a method that can be used continuously for many years.

On the other hand, as a method for separating and recovering radioactive substances in the suspension, for example, as shown in Patent Document 1, there is a method in which solid particles are formed by adding a flocculant to the suspension, and this is separated and recovered. is there.
This method is used for turbid water generated by washing rice husk and the like to which soil particles containing radioactive metal material are attached in the field, and the radioactive metal material is contained by adding a flocculant to the turbid water and stirring. The soil particles containing the radioactive metal substance can be separated and recovered by solidifying the soil particles and filtering the solidified soil particles with a filter medium.

Special table 2012-507000 gazette

  However, the method of solidifying and collecting soil particles containing radioactive metal substances in muddy water using an aggregating agent means that the used flocculant is contained in the separated and recovered solid, and generally the soil particles are treated. In order to do so, a large amount of flocculant is required, which increases the amount of radioactive waste.

  In addition, soil particles in turbid water include large-diameter soil particles that do not contain radioactive substances, so these are also included in the separated and recovered solids. Otherwise, there is a problem that the amount of radioactive waste increases dramatically.

  In addition, in order to separate the soil particles solidified by the flocculant from the treated water with reduced radioactive substances, a step of filtering with a filtering agent is required, and the used filtering agent becomes radioactive waste. There is a problem of further increasing the amount of radioactive waste.

  Therefore, the object of the present invention is to efficiently separate and collect fine particles containing radioactive metal substances from turbid water containing contaminated soil particles without using adsorbents or flocculants, thereby reducing the amount of radioactive waste. It is providing the collection | recovery apparatus and collection | recovery method which can be performed.

In order to solve the above-mentioned problem, the fine particle recovery device containing radioactive metal substance in muddy water according to the present invention collects fine particles containing radioactive metal substance from contaminated muddy water without using an adsorbent or a flocculant. A bubble contact cylinder that makes fine bubbles contact with the supplied water to be treated, attaches fine particles containing the radioactive metal substance to the fine bubbles, and floats, and is formed in a reverse funnel shape, Connected to the upper part of the bubble contact cylinder, a floc aggregation cylinder for agglomerating fine particles containing a radioactive metal substance adhering to the fine bubbles and floating as a floc, and connected to the upper part of the floc aggregation cylinder, A floc collecting cylinder for accumulating and collecting the aggregated flocs and a flock accumulated in the flock collecting cylinder connected to the lower part of the flock collecting cylinder are discharged. A floc collecting section having a floc discharge pipe and a fine particle containing a radioactive metal substance that is connected to the upper portion of the floc collecting cylinder and floats on the fine bubbles is collected by foam generated on the liquid surface. A foam recovery unit having a foam recovery cylinder and a foam recovery container for containing the foam overflowed from the foam recovery cylinder, and formed in a funnel shape, connected to the lower part of the bubble contact cylinder, to the supplied treated water Supplied water is supplied into a tank formed by a sedimentation cylinder that sediments large-diameter particles contained therein and collects the sediment as a sediment from the lower part, the bubble contact cylinder, the floc aggregation cylinder, the sedimentation cylinder, and the floc collection cylinder. A treated water supply pipe, a fine bubble generating means for generating the fine bubbles in the treated water in the tank, a treated water recovery pipe for collecting the treated water from the tank, Supply of water to be treated into the tank through the water supply pipe to be treated, generation of fine bubbles by the fine bubble generating means, recovery of floc from the flock recovery pipe, recovery of sediment from the lower part of the settling cylinder, and And a control means for controlling at least a part of the recovery of the treated water in the tank from the treated water recovery pipe.
According to the present invention, in the bubble contact cylinder, by bringing the fine bubbles into contact with the water to be treated, the fine particles containing the radioactive metal substance are attached to the fine bubbles and floated, and the floc aggregation cylinder is formed on the upper part of the bubble contact cylinder. In the foam recovery tube connected via the flock recovery cylinder, the fine particles containing the radioactive metal material that floats by adhering to the fine bubbles are recovered by the foam generated on the liquid surface. The amount of radioactive waste can be reduced by efficiently recovering the contained radioactive material.
Further, according to the present invention, in the floc aggregation cylinder connected to the upper part of the bubble contact cylinder, the fine particles containing the radioactive metal material that floats by adhering to the fine bubbles are formed in a reverse funnel shape whose diameter is reduced upward. As the flocs with high particle density are agglomerated by floating inside the cylinder, the floc collection cylinder connected to the upper part of the floc aggregation cylinder accumulates the aggregated flocs and collects them from the floc collection pipe. Fine particles containing radioactive metal substances that do not float up to the foam collection cylinder due to fine bubbles can be collected as flocs with a low water content without using a flocculant, and the radioactive substances contained in the water to be treated can be collected more efficiently. Thus, the amount of radioactive waste can be further reduced.
Further, according to the present invention, in the sedimentation cylinder connected to the lower part of the bubble contact cylinder, the large-diameter particles contained in the supplied water to be treated are settled in the funnel-shaped cylinder whose diameter is reduced downward. Since the sediment is collected from the lower part, the large-diameter particles containing almost no radioactive metal substance can be separated and recovered as reusable soil particles.
As described above, according to the present invention, since the foam collecting unit, the flock collecting unit, and the settling cylinder are provided, the collection of the fine particles containing the radioactive metal material by the foam, and the fine particles containing the radioactive metal material by the flock. Recovery, recovery of large particles containing almost no radioactive metal material, and recovery of treated water containing almost no radioactive metal material can be performed simultaneously in the treatment in a single tank. Fine particles containing a radioactive metal substance can be efficiently recovered and separated into those that should be disposed of as radioactive waste and those that can be reused.

The fine particle recovery device containing radioactive metal substance in muddy water according to the present invention is a tank for accumulating the treated water supplied into the tank, and the water level of the treated water in the tank is the floc recovery. A constant water level tank having a water level adjusting means for adjusting so as to coincide with the upper end of the cylinder is provided on the upstream side of the treated water supply pipe.
According to this invention, since the water level of the water to be treated in the tank is adjusted so that the level of the water to be treated in the tank coincides with the upper end of the flock recovery cylinder, it is supplied to the tank. The water level of the water to be treated is automatically adjusted so as to be at the upper end of the floc collecting cylinder, and the aggregated floc can be appropriately accumulated and collected in the flock collecting cylinder.

Further, the fine particle recovery apparatus containing the radioactive metal substance in muddy water according to the present invention includes a sediment recovery cylinder that takes in the sediment settled in the sedimentation cylinder and accumulates a predetermined amount in the lower part of the sedimentation cylinder, and the sedimentation A sediment recovery unit having a sediment recovery valve for taking the sediment in the cylinder into the sediment recovery cylinder and a sediment discharge valve for discharging the sediment accumulated in the sediment recovery cylinder to the outside; is there.
According to the present invention, a sediment recovery cylinder for recovering the sediment precipitated in the sedimentation cylinder is provided at the bottom of the sedimentation cylinder, the sediment recovery valve for taking the sediment in the sedimentation cylinder into the sediment recovery cylinder, and the sediment recovery Since it has a sediment discharge valve that discharges the sediment accumulated in the cylinder, it is possible to collect a certain amount of sediment from the sedimentation cylinder by closing the sediment discharge valve and opening the sediment recovery valve. And the outflow of treated water in the tank can be prevented.

Further, the fine particle recovery apparatus containing the radioactive metal substance in muddy water according to the present invention is the vibration generating means for applying vibration to the settling cylinder in the settling cylinder in order to remove the deposits attached to the inner surface of the settling cylinder. The control means has a function of closing the sediment discharge valve, opening the sediment recovery valve, and controlling the vibration generating means to operate for a predetermined time.
According to this invention, the vibration generating means for applying vibration to the sedimentation cylinder is provided, the sediment discharge valve is closed, the sediment recovery valve is opened, and the vibration generation means is operated for a predetermined time to adhere to the inside of the sedimentation cylinder. The deposited precipitate can be discharged accurately.

Further, the fine particle recovery apparatus containing the radioactive metal substance in muddy water according to the present invention is the microbubble generating means for generating microbubbles in the water to be treated in the tank and supplying the microbubbles in the tank. Means and nanobubble generating means for generating nanobubbles in the water to be treated in the tank and supplying the nanobubbles to the tank.
According to the present invention, since the microbubble generating means for generating microbubbles and the nanobubble generating means for generating nanobubbles are combined as the fine bubble generating means, the radioactive metal is produced by the aggregation effect of the nanobubbles in the bubble contact cylinder. Fine particles containing substances can be agglomerated, and fine particles containing agglomerated radioactive metal substances can be levitated by the adsorption and floating effect of microbubbles. In the floc aggregation cylinder formed on the reverse funnel, the particle density is higher. High flocs can be formed, and the amount of radioactive waste can be further reduced.

Further, the fine particle recovery apparatus containing the radioactive metal substance in muddy water according to the present invention is generated by the microbubble supply pipe for supplying the microbubbles generated by the microbubble generating means into the tank and the nanobubble generating means. The nanobubble supply pipe for supplying the nanobubbles into the tank is provided at an opposing position on the outer periphery of the bubble contact cylinder and configured to suppress the generation of swirling flow in the bubble contact cylinder It is.
According to the present invention, the microbubble supply pipe for supplying the microbubbles into the tank and the nanobubble supply pipe for supplying the nanobubbles into the tank are provided at opposite positions on the outer periphery of the bubble contact tank. It is possible to suppress the swirling flow generated by supplying the gas into the inside, to enhance the floating effect of the fine particles containing the radioactive metal material due to the fine bubbles, and to form a floc with a higher particle density. The amount can be further reduced.

Moreover, the fine particle collection | recovery apparatus containing the radioactive metal substance in muddy water concerning this invention is provided with the swirl flow suppression board which suppresses generation | occurrence | production of the swirl | vortex flow in the said bubble contact cylinder in the said bubble contact cylinder.
According to the present invention, since the swirl flow suppressing plate for suppressing the swirl flow generation is provided in the bubble contact cylinder, the swirl flow generation in the bubble contact cylinder by the fine bubble generating means can be suppressed. The floating effect of the fine particles containing the radioactive metal substance due to the fine bubbles can be enhanced, flocs with higher particle density can be formed, and the amount of radioactive waste can be further reduced.

Further, the fine particle recovery device containing radioactive metal substance in muddy water according to the present invention comprises a flock monitoring sensor for monitoring the generation state of flock accumulated in the flock recovery cylinder in the flock recovery section, and the control means The floc monitoring sensor detects that flocks are accumulated in the flock collection cylinder, and controls to collect the flocks accumulated in the flock collection cylinder from the flock collection pipe. Is.
According to the present invention, the state of floc generation in the flock collecting cylinder is monitored by the flock monitoring sensor, and when it is detected that the flock is accumulated in the flock collecting cylinder, the flock provided at the lower part of the flock collecting cylinder is detected. Since the collection pipe is opened and the floc accumulated in the flock collection cylinder is collected, the flock accumulated in the flock collection cylinder can be collected accurately.

Moreover, the fine particle recovery apparatus containing the radioactive metal substance in the muddy water according to the present invention provides a foaming aid supply for supplying a foaming aid for promoting foam generation to the treated water supplied into the tank. A foam generation status monitoring sensor for monitoring the foam generation status in the foam recovery unit, and the control means monitors the foam generation status after a lapse of a predetermined time after operating the fine bubble generating means. When the generation of the predetermined foam is not detected by the sensor, it has a function of operating the foaming aid supplying means.
According to the experiments by the inventors, the washed polluted water obtained by washing the soil particles containing the radioactive metal substance attached to the rice husk has a large difference in the state of foam generation due to the nature of the soil in the collected field. It has been confirmed that sufficient foam may not be generated by fine bubbles.
For this reason, according to the present invention, the foam generation state in the foam collection cylinder is monitored by the foam monitoring sensor, and after a predetermined time has elapsed since the fine bubble generating means is operated, the generation of the predetermined foam in the foam collection cylinder is detected. In the case where the foaming aid is not supplied, the foaming aid is supplied into the tank by the foaming aid supply means. Therefore, it is sufficient to supply the foaming aid even for turbid water collected from soil where foam is not sufficiently formed. Bubbles can be generated, and the fine particles containing the radioactive metal material by the bubbles can be accurately recovered.

Further, the fine particle collecting apparatus containing radioactive metal substance in muddy water according to the present invention is the control means, wherein the fine bubble generating means is stopped after operating for a predetermined time, and a high-concentration floc generated after the stop is stopped. It has a function to control to collect.
According to the experiments by the inventors, when the fine bubble generating device is activated and foam is generated, the foam recovery cylinder is in a state of being covered with the foam, and the floc aggregation cylinder and the floc recovery cylinder are loose. Although the floating upstream is formed, when the generation of fine bubbles is stopped, the air in the pressurized tank in the fine bubble generator expands instantaneously, so the foam in the foam collection cylinder overflows all at once, Since the lid is removed, the excessively dissolved air in the tank rises in the form of bubbles one after another, and a clear floating upstream is formed compared to before the stop of the fine bubbles. Was confirmed. And since the air bubbles take in the soil particles and the flocs grow rapidly due to this fast floating upstream, and the flocs that have grown are settled against the flow in the floc collecting cylinder, and a good convection occurs, so the concentration is extremely high. It was confirmed that a high floc was formed.

For this reason, according to the present invention, since the fine bubble generating means is operated for a predetermined time and then stopped, the high-density flocs generated after the stop are recovered, so that the high concentration can be achieved in a short time. The condensed floc can be recovered.

Further, the fine particle recovery device containing radioactive metal material in muddy water according to the present invention comprises a plurality of fine particle recovery devices containing radioactive metal material in muddy water, and the fine particles containing the radioactive metal material in muddy water in each stage A lower part of the floc coagulation cylinder of the recovery device is provided with an aggregate water recovery pipe for recovering the treated water of the floc aggregation cylinder after the completion of the floc recovery by the flock recovery section as coagulated water, Cascade connection was performed so that the aggregated water recovered from the aggregated water recovery pipe of the fine particle recovery apparatus containing the radioactive metal substance was supplied as the treated water of the fine particle recovery apparatus including the radioactive metal substance in the turbid water in the subsequent stage. Is.
In the fine particle collection device containing radioactive metal material in turbid water, the fine particle containing the radioactive metal material by foam and the collection of fine particles containing the radioactive metal material by flocking, As a result, fine particles containing a radioactive metal material that cannot be floated and separated by flocs and not agglomerated as floc remain.
Therefore, according to the present invention, a plurality of fine particle recovery devices containing radioactive metal substances in muddy water are provided in a plurality of stages, and the aggregated water recovered from the aggregated water recovery pipe provided in the lower part of the front floc aggregation cylinder is collected in the latter stage. Since cascade connection is made so that it is supplied as treated water, fine particles containing radioactive metal material that could not be recovered by a single recovery device can be concentrated and recovered by a multi-stage recovery device. The amount of the radioactive substance of the treated water collected can be drastically reduced.

The method for recovering fine particles containing a radioactive metal substance in muddy water according to the present invention is a method in which fine bubbles are brought into contact with the supplied water to be treated, and the fine particles containing the radioactive metal substance are attached to the fine bubbles to float. A contact cylinder, a flock aggregation cylinder formed in a reverse funnel shape, connected to an upper portion of the bubble contact cylinder, and agglomerating flocs of fine particles containing a radioactive metal substance generated by the fine bubbles; and the floc aggregation cylinder A flock collecting cylinder connected to the upper part for accumulating and collecting the flocs aggregated by the flock collecting cylinder, and a flock discharge connected to the lower part of the flock collecting cylinder for discharging the flocs accumulated in the flock collecting cylinder A flock collecting section having a tube and connected to an upper portion of the flock collecting cylinder, and the floc collecting without being aggregated by the flock collecting cylinder A foam recovery cylinder for recovering fine particles containing the radioactive metal material that has floated through the foam by foam generated on the liquid surface by the fine bubbles, and a foam recovery container for storing the foam overflowing from the foam recovery cylinder A foam recovery unit having a funnel-like shape, connected to the lower part of the bubble contact cylinder, sedimenting large-diameter particles contained in the supplied water to be treated, and recovering from the lower part as a precipitate; A treated water supply pipe for supplying treated water into a tank formed by the bubble contact cylinder, the floc aggregation cylinder, the settling cylinder, and the flock collecting cylinder, and the fine bubbles in the treated water in the tank. Using a fine particle recovery device containing a radioactive metal substance in muddy water, comprising a fine bubble generating means to be generated and a treated water collection pipe for collecting treated water from the tank, the adsorbent and coagulant are collected. A method for recovering fine soil particles containing radioactive metal substances from contaminated turbid water without using a chemical agent, comprising supplying treated water from the treated water supply pipe into the tank, A step of setting the water level of the treated water at the upper end of the flock collecting cylinder, a step of operating the fine bubble generating means to generate fine bubbles in the bubble contact cylinder, and flocks accumulated in the flock collecting cylinder. When it is confirmed that the floc accumulated in the floc collecting cylinder is collected from the flock collecting tube, and the foam is collected when the amount of foam accumulated in the foam collecting container reaches a predetermined amount. A step, a step of recovering a precipitate precipitated in the settling tube from a lower portion of the settling tube, a step of recovering the floc by the step of recovering the floc, and a step of recovering the precipitate by the step of recovering the precipitate And the step of recovering the treated water in the tank after the end.
According to this invention, the collection of fine particles containing radioactive metal material by foam, the collection of fine particles containing radioactive metal material by floc, the collection of large-diameter particles almost free of radioactive metal material, and the radioactive metal material Can be performed simultaneously in the treatment in a single tank, and fine particles containing radioactive metal substances can be efficiently recovered from turbid water. It can be separated into what should be disposed of and what can be reused.

In addition, the method for recovering fine particles containing radioactive metal substances in muddy water according to the present invention is a method for cleaning contaminated water obtained by washing rice husks or the like to which soil particles containing radioactive metal substances are attached in a contaminated field with washing water, A step of supplying as treated water, and a step of reusing the treated water collected by the step of collecting treated water in the tank as washing water for washing the rice husk and the like.
This invention collects soil particles containing a radioactive metal substance using rice husk etc. in a contaminated field, and the soil particles containing a radioactive metal substance adhering to the rice husk etc. are washed with washing water, so that This is used in a processing method for reusing rice husk etc. for the recovery of soil particles containing radioactive metal substances in the field, and the contaminated washing water produced by washing the rice husk etc. is covered with the collecting device of this invention. Since the treated water is supplied as treated water and the fine particles containing the radioactive metal substance are collected by the collection device of the present invention, the treated water is reused as washing water for washing rice husks, etc. It can be processed efficiently without generation.

Further, the method for recovering fine particles containing radioactive metal substance in muddy water according to the present invention provides a predetermined recovery time in the foam recovery section after a predetermined time has elapsed since the microbubble generating means was activated in the step of generating the microbubbles. When the generation of foam is not confirmed, the method further includes a step of introducing a foam generation aid into the tank.
According to this invention, the foaming aid is supplied into the tank by the foaming aid supply means when the generation of the predetermined foam is not confirmed in the foam collection cylinder after a predetermined time has elapsed since the fine bubble generating means was activated. Since it is equipped with a process, even if it is turbid water collected from soil where foam is not sufficiently formed by fine bubbles, sufficient foam is generated by supplying a foaming aid, and the fine particles containing radioactive metal substances due to foam are generated. Recovery can be performed accurately.

Further, the method for recovering fine particles containing a radioactive metal substance in muddy water according to the present invention is a step of recovering the floc in the step of generating the fine bubbles by stopping the fine bubble generating means after operating for a predetermined time. The high-floc floc produced after the fine bubble generating means is stopped is recovered.
According to the present invention, the fine bubble generating means is stopped after operating for a predetermined time, and the high-concentration floc generated as described above is recovered, so that it is condensed to a high concentration in a short time. Flock can be recovered.

Moreover, the fine particle recovery method including the radioactive metal substance in muddy water according to the present invention includes a plurality of stages of the fine particle recovery device including the radioactive metal substance in the muddy water, and the fine particle including the radioactive metal substance in the muddy water in each stage. Radioactivity in turbid water with a flocculent water collecting pipe for collecting the treated water of the floc flocculant cylinder after the floc collection by the floc collecting section as the condensed water is provided at the lower part of the floc flocculant cylinder of the particle collecting apparatus. A method for recovering fine particles containing radioactive metal material in muddy water using a fine particle recovery device containing metal substance, the aggregated water recovery pipe of the fine particle recovery device containing the radioactive metal substance in muddy water in the previous stage A step of supplying the recovered condensed water as the water to be treated of the fine particle recovery device containing the radioactive metal substance in the muddy water in the subsequent stage is provided.
According to the present invention, a plurality of fine particle recovery devices containing radioactive metal substances in muddy water are provided in a plurality of stages, and the aggregated water recovered by the aggregated water recovery pipe provided at the lower part of the front floc aggregation cylinder is used as the post-treatment water. Since the supplying step is provided, it is possible to efficiently recover the fine particles containing the radioactive metal substance, and to dramatically reduce the amount of the radioactive substance of the treated water collected from the treated water collection pipe.

  According to the present invention, fine particles containing radioactive metal material can be collected from contaminated turbid water without using an adsorbent or a flocculant, and the collection of fine particles containing radioactive metal material by foam and flocking The collection of fine particles containing radioactive metal materials, the collection of large particles containing almost no radioactive metal materials, and the recovery of treated water containing almost no radioactive metal materials are possible in a single tank. It can be performed at the same time, and turbid water contaminated with fine particles containing a radioactive metal substance can be treated efficiently.

  The above-described object, other objects, features, and advantages of the present invention will become more apparent from the following description of embodiments for carrying out the invention with reference to the drawings.

It is an illustration figure which shows schematic structure of the fine particle collection | recovery apparatus containing the radioactive metal substance in muddy water concerning one Embodiment of this invention. It is a flowchart which shows an example of the control procedure by the control apparatus of the fine particle collection apparatus containing the radioactive metal substance in muddy water concerning one Embodiment of this invention. It is an external appearance photograph (first half part of the collection process of a panoramic photograph and foam) of the experimental apparatus of the fine particle collection apparatus containing the radioactive metal substance in the muddy water concerning one Embodiment of this invention. It is an external appearance photograph (the latter half part of the collection process of foam) of the experimental apparatus of the fine particle collection apparatus containing the radioactive metal substance in the muddy water concerning one Embodiment of this invention. It is an external appearance photograph (floc recovery process) of an experimental device of a fine particle recovery device containing a radioactive metal substance in muddy water according to an embodiment of the present invention.

FIG. 1 shows a schematic configuration of a fine particle recovery apparatus containing a radioactive metal substance in muddy water according to an embodiment of the present invention.
The fine particle collection device containing the radioactive metal substance in muddy water according to one embodiment of the present invention is roughly divided into a foam collection unit 10, a flock collection unit 20, a flock aggregation unit 30, a bubble contact unit 40, a settling unit 50, It comprises a sediment collection unit 60, a treated water supply unit 70, a fine bubble generation unit 80, a foaming aid addition unit 90, and a control device 100.

The bubble contact part 40 is a part which makes the supplied to-be-processed water contact a fine bubble, and is provided with the bubble contact cylinder 42 formed in the substantially cylindrical shape. When the fine bubbles come into contact with the water to be treated in the bubble contact cylinder 32, the fine particles containing the radioactive metal substance in the water to be treated adhere to the fine bubbles and float.
The microbubble contact cylinder 42 is preferably formed of a transparent member so that the state in the tank being processed can be observed.

The floc aggregation part 30 is a part for agglomerating fine particles containing a radioactive metal substance that adheres to the fine bubbles and floats as a floc. The floc aggregation part 30 is formed in a reverse funnel shape and is connected to the upper part of the bubble contact cylinder 42. 32. Since the floc aggregation cylinder 32 is formed in a reverse funnel shape that is reduced in diameter toward the upper side, the flocs of fine particles containing a radioactive metal material generated by the fine bubbles pass through the inside of the cylinder formed in the reverse funnel shape. By floating, flocs with high particle density are formed.
The floc aggregation cylinder 32 is also preferably formed of a transparent member so that the inside of the tank being processed can be observed.
Under the floc aggregation cylinder 32, the aggregation water for collecting the aggregated water in the clock aggregation cylinder 32 immediately after the collection of the fine particles containing the radioactive metal material by the foam and the collection of the fine particles containing the radioactive metal material by the flock is completed. A recovery tube 34 is provided. The floc-aggregating cylinder immediately after the collection of fine particles containing radioactive metal material by foam and the collection of fine particles containing radioactive metal material by floc cannot be floated and separated by fine bubbles, and the radioactive material that has not been agglomerated as floc Since fine particles containing a metal substance remain, the amount of radioactive substances in the treated water can be further reduced by separating and collecting the fine particles. Moreover, the amount of radioactive substances in the treated water can be drastically reduced by providing a plurality of collecting devices and supplying the condensed water collected in the preceding stage as the to-be-treated water.

The flock collecting unit 20 is a part that collects the flocs that are aggregated and floated in the flock aggregation unit 30, and is connected to the upper part of the flock aggregation cylinder 32 and accumulates the aggregated flocs that float from the flock aggregation cylinder 32. A tube 22 is provided. Here, the inner diameter of the flock collecting cylinder 22 is made larger than the inner diameter of the foam collecting cylinder 12 described later in order to increase the volume of the accumulated flock, but it may be the same as the inner diameter of the foam collecting cylinder.
The flock collecting cylinder 22 is also preferably formed of a transparent member so that the state in the tank being processed can be observed.
Below the flock collecting cylinder 22, a flock collecting pipe 24 for collecting the flock accumulated in the flock collecting cylinder 22 is provided.
In addition, the flock collecting unit 20 includes a flock monitoring sensor 26 for monitoring a flock generation state in the flock collecting cylinder 22. If it is detected by the flock monitoring sensor 26 that flocks are accumulated in the flock collecting cylinder 22, the accumulated flocks can be efficiently collected by opening the flock collecting valve 25.
Since the portion where the floc is accumulated in the flock collecting cylinder 22 forms a dark brown layer, a flock monitoring sensor can be configured by a television camera that images the flock collecting cylinder 22 formed of a transparent member. . In this case, it is possible to determine the range where the flock is formed by performing image processing on the video signal from the television camera and detecting a difference in luminance or a difference in color tone between the upper and lower sides. Note that the television camera does not necessarily have to capture a two-dimensional image, and a line sensor that captures a one-dimensional image in the vertical direction can also be used.
Further, since the turbidity of the water to be treated is different between the part where the floc is accumulated in the flock collecting cylinder 22 and the other part, the change in the amount of transmitted light transmitted through the flock collecting cylinder 22 formed of a transparent member is detected. By doing so, it is also possible to monitor the state of floc generation in the floc collecting cylinder 22. In this case, the light projector and the light receiver are provided at portions facing each other at a plurality of positions in the vertical direction of the flock collecting cylinder 22, and the flocs are accumulated in the flock collecting cylinder 22 by comparing the signal levels of the respective light receiving devices relative to each other. This may be detected by providing a line sensor along the vertical direction of the flock collecting cylinder 22, receiving the transmitted light from the projector provided in the opposite direction by the line sensor, and signaling a one-dimensional signal from the line sensor By processing, a range where the floc is formed in the floc collecting cylinder 22 may be detected, and the floc monitoring sensor can be configured using various detection devices.

The foam collection unit 10 is a part that collects fine particles containing a radioactive metal material that floats by adhering to fine bubbles in the floc aggregation cylinder 32 by foam generated on the liquid surface. It is connected and includes a foam collecting cylinder 12 for collecting foam generated on the liquid surface.
The foam collecting cylinder 12 is also preferably formed of a transparent member so that the state in the tank being processed can be observed.
In the upper part of the foam collection cylinder 12, a foam collection container 14 that accommodates the foam overflowing from the foam collection cylinder 12 is provided.
In addition, in the foam collection unit 10, in order to determine whether or not sufficient foam is generated in the foam collection cylinder 12 so that the fine particles containing the radioactive metal material by the foam can be collected. A foam monitoring sensor 16 is provided. When the foam monitoring sensor 16 detects that a sufficient amount of foam is not formed in the foam collection cylinder 12, the foam assistant is added to the water to be treated by the foam assistant addition unit 90 described later. Thus, it is possible to generate a predetermined foam also for the washed contaminated water collected from the soil that is difficult to foam due to the fine bubbles, and to reliably collect the fine particles containing the radioactive metal substance by the foam.
The part where the foam is generated in the foam recovery cylinder 12 is a rough part due to the foam. Therefore, the part near the liquid surface of the flock recovery cylinder 22 or the lower part of the foam recovery cylinder 12 formed of a transparent material is used. A TV camera for imaging is provided, and the video signal is subjected to image processing, and the generation state of foam can be determined by detecting the occurrence of a rough portion due to bubbles. In this case, the vicinity of the liquid level of the flock collecting cylinder 22 is imaged by a television camera, and the generation of foam is determined by comparing the texture of the image below the liquid level with the texture of the image on the liquid level. Also good.
Also in this case, a line sensor that captures a one-dimensional image can be used as in the above-described flock monitoring sensor 26, and light is received using a transmission type light sensor or a reflection type light sensor using a projector and a light receiver. The generation of foam may be determined by detecting the change in the signal of the detector, and a transmission type optical sensor or a reflection type optical sensor is provided both above and below the liquid level, and the signal of each receiver is received. A relative comparison may be made to determine the generation of foam, and the foam monitoring sensor can be configured using various detection devices.

The sedimentation part 50 is a part that sediments as a sediment to collect large-sized particles or the like that hardly contain radioactive metal substances in the water to be treated. The sedimentation part 50 is formed in a funnel shape and is connected to the lower part of the bubble contact cylinder 42. A settling cylinder 52 is provided. Since the sedimentation cylinder 52 is formed in a funnel shape whose diameter is reduced downward, large-diameter particles containing almost no radioactive metal substance in the water to be treated are aggregated as precipitates at the lower part of the sedimentation cylinder.
The sedimentation cylinder 52 is also preferably formed of a transparent member so that the state in the tank being processed can be observed.
The settling cylinder 52 is provided with a vibration generating device 54 that vibrates the settling cylinder 52 in order to promote the discharge of the deposit attached to the inside from the lower part.
In addition, in the sedimentation part 50, the collection of the fine particles containing the radioactive metal material by the foam and the collection of the fine particles containing the radioactive metal material by the flock are completed, and the treated water almost containing no radioactive material is collected. A treated water recovery pipe 56 is provided.

The sediment collection unit 60 collects the sediment that has settled in the sedimentation cylinder 52 and includes a sediment collection cylinder 62 that accumulates the sediment discharged from the sedimentation cylinder 52.
An upper part of the sediment collection cylinder 62 is connected to the lower part of the sedimentation cylinder 52 and includes a sediment recovery valve 64 for recovering the sediment from the sedimentation cylinder 52. A sediment discharge valve 66 for discharging the sediment accumulated in the recovery cylinder 62 to the outside is provided.
Therefore, by closing the sediment discharge valve 66 and opening the sediment recovery valve 64, a predetermined amount of the sediment precipitated in the sedimentation cylinder 52 is recovered without causing the treated water in the tank to flow out. It can be collected in the cylinder 62.
The sediment stored in the sediment recovery cylinder 62 can be taken out by closing the sediment recovery valve 64 and opening the sediment discharge valve 66, and if there is no problem after measuring the radiation dose, Can be reused.

The to-be-treated water supply unit 70 uses the turbid water (washed contaminated water) collected by washing rice husks, etc. as the to-be-treated water from the bubble contact cylinder 42, the flock aggregation cylinder 32, the flock collection cylinder 22, and the settling cylinder 52. It supplies to the tank comprised, and is equipped with the constant water level tank 72 provided with the water level regulators 75, such as a ball tap.
In the constant water level tank 72, cleaning contaminated water introduction pipe 74 that supplies separately accumulated muddy water (cleaning contaminated water) to the constant water level tank 72, and water to be treated that supplies the water to be treated in the constant water level tank 72 into the tank. A supply pipe 76 is connected.
The water level adjuster 75 is for setting the water level of the water to be treated supplied into the tank at the upper end of the flock collecting cylinder 22, and the water level of the constant water level tank 72 adjusted by the water level adjuster 75 is the flock recovered. It is set to coincide with the upper end of the cylinder. Thereby, when the to-be-treated supply valve 75 of the to-be-treated water supply pipe 76 is opened, the to-be-treated water is supplied into the tank so that the level of the to-be-treated water in the tank coincides with the upper end of the flock collecting cylinder 22. Automatically adjusted to.

The fine bubble generating unit 80 supplies fine bubbles to the water to be treated in the tank, and generates a nano bubble in the water to be treated in the tank, and generates a micro bubble in the water to be treated in the tank. A microbubble generator 86 to be provided.
The nanobubble generator 82 is connected to a nanobubble water absorption pipe 83 that sucks in the water to be treated in the tank for generating nanobubbles, and a nanobubble supply pipe 84 that supplies the water to be treated in which the nanobubbles are generated into the tank.
The microbubble generator 86 includes a microbubble water absorption pipe 87 for sucking water to be treated in the tank for generating microbubbles, and a microbubble supply pipe 88 for supplying the water to be treated in which microbubbles are generated to the tank. Connected.
The nanobubbles generated by the nanobubble generator 82 have a particle size of less than 1 μm and have a function of aggregating fine particles containing a radioactive metal substance. The microbubbles generated by the microbubble generator 86 have a particle size of Is about 1 to 100 μm, and has the function of floating fine particles containing a radioactive metal substance aggregated by nanobubbles, so that fine particles containing a wide range of radioactive metal substance can be levitated and collected.
The nanobubble supply pipe 84 for supplying nanobubbles into the tank and the microbubble supply pipe 88 for supplying microbubbles into the tank generate a swirling flow in the tank by the supply of nanobubbles and the supply of microbubbles into the tank. In order to suppress this as much as possible, it is installed in the opposing direction of the outer periphery of the lower part of the bubble contact tube 42.

The foaming auxiliary agent adding unit 90 adds a foaming auxiliary agent when the foam collecting unit 12 does not generate foam necessary for collecting fine particles containing the radioactive metal material by the foam. A foaming aid mixer 92 for adding to the treated water is provided.
Connected to the foaming aid mixer 92 are a foaming support water absorption pipe 93 that absorbs the water to be treated in the tank, and a foaming aid supply pipe 94 that supplies the water to be treated with the foaming aid added to the tank. When the generation of foam in the foam recovery unit by the fine bubble generating unit 80 is not sufficient, the water to be treated is mixed with the water to be treated in the tank, and the water to be treated to which a necessary amount of the foaming aid is added. Returned to the tank.
The foaming aid may be any natural product that is biodegraded by microorganisms after returning the large-diameter particles taken out from the sediment recovery unit to the field, etc., and promotes foaming of water to be treated. For example, a protein-containing agent such as wheat flour can be used.

The control device 100 controls the control target of each part in order to perform the recovery processing of the fine particles containing the radioactive metal substance using the recovery device configured as described above. Water to be treated into the tank, operation of the nanobubble generator 82 and microbubble generator 86, recovery of floc from the flock recovery pipe 24, recovery of sediment from the sedimentation cylinder 52, addition of foaming aid, etc. Is controlled.
The control device 100 can be configured using a sequencer, a microcontroller, a microcomputer, or the like that is used to control general industrial products.

In FIG. 2, an example of the control procedure of the control apparatus 100 of the fine particle collection apparatus containing the radioactive metal substance in the muddy water concerning the said embodiment is shown.
As shown in the figure, first, the treated supply valve 77 of the treated water supply pipe 76 is opened, and the treated water is supplied to the upper end of the flock collecting cylinder 22 in the tank (S102). Since the recovery device of this embodiment includes the constant water level tank 72, the water level in the tank is automatically adjusted to the upper end of the flock recovery cylinder 22.

  When the water to be treated is supplied to the upper end of the flock collecting cylinder 22 in the tank, the nanobubble generator 82 and the microbubble generator 86 are activated to generate fine bubbles in the tank (S104). Here, the fact that the water to be treated has been supplied up to the upper end of the flock collecting cylinder 22 in the tank can be detected by, for example, the operation status of the water level adjuster 75 of the constant water level tank 72. You may make it start generation | occurrence | production of a microbubble after progress of the time required to do or predetermined time before it.

  When a predetermined time elapses after the generation of the fine bubbles (S106), the foam monitoring sensor 16 confirms the generation state of the foam in the foam collecting cylinder 12, and when a predetermined amount of foam is not detected (S108), the firing aid mixing The device 92 is activated and a firing aid is added to the water to be treated (S110). The predetermined time here is normally set to the time from when fine bubbles are generated until a predetermined amount of foam is formed in the foam collecting cylinder 12. The amount of foam generated can be determined based on the signal from the foam monitoring sensor 16 by calculating the area of the rough portion or detecting the duration of signal change.

  Thereafter, when a predetermined time has elapsed (S112), the nanobubble generator 82 and the microbubble generator 86 are stopped (S114). As a result, the foam generated in the foam collection cylinder 12 overflows at once and is collected in the foam collection container 14, and an early floating upstream is formed in the flock aggregation cylinder 32. Growing rapidly, flocs with high concentration are accumulated in the floc collecting cylinder 22. The predetermined time here is usually set to a time required for collecting fine particles containing the radioactive metal material by foam.

Here, when it is detected by the flock monitoring sensor 26 that flocks are accumulated in the flock collecting cylinder 22 (S116), the flock collecting valve 25 of the flock collecting pipe 24 is opened and accumulated in the flock collecting cylinder 22. The flock is collected (S118).
Such flock collection from the flock collection cylinder 22 is repeated for a predetermined time (S120). The predetermined time here is set to a time sufficient to collect the floc accumulated in the flock collecting cylinder 22 in the normal floc collection.
In the monitoring of the generation state of the floc by the floc monitoring sensor 26, when the height of the floc accumulated in the floc collecting cylinder 24 is continuously detected and the detected floc height is no longer changed. The floc accumulated in the flock collecting cylinder 24 may be collected by opening the flock collecting valve 25 of the flock collecting pipe 24, assuming that the generation of the flock has been completed.

Next, when it is confirmed that the foam is accumulated in the foam collection container 14 of the foam collection unit (S122), the foam accumulated in the foam collection container 14 is collected (S124). Since the foam disappears and liquefies over time, the foam can be recovered by opening the foam recovery valve (not shown) of the foam recovery container 14.
In addition, in order to accelerate | stimulate collection | recovery of foam, the sprayer which sprays a mist-like water droplet may be provided in the foam collection | recovery container 14, and you may make it defoam forcibly. Thereby, the soil particles remaining in the foam collection container 14 after the foam is collected can be washed away and collected.

  When the recovery of the floc and the necessary foam are completed, the aggregated water recovery valve 35 of the aggregated water recovery pipe 34 is opened, and the aggregated water in the floc aggregation cylinder 32 is recovered (S126).

Next, in order to collect large-diameter particles and the like that hardly contain radioactive metal material precipitated in the sedimentation cylinder 52, the sediment discharge valve 66 of the sediment collection cylinder 62 is closed, the sediment recovery valve 64 is opened, The vibration generating device 54 of the sedimentation cylinder 52 is activated for a predetermined time, and the sediment in the sedimentation cylinder 52 is recovered in the sediment recovery cylinder 62 (S128).
The sediment collected in the sediment collection cylinder 62 can be taken out by closing the sediment collection valve 64 and opening the sediment discharge valve 66. If there is no problem in measuring the radiation dose, Can be reused.

  Finally, in order to collect the treated water after the treatment, the sediment collecting valve 64 is closed, and the treated water collecting valve 57 of the treated water collecting pipe 56 is opened, so that most of the radioactive metal substance in the tank is contained. Untreated water can be recovered (S130). The treated water collected in this manner can be reused as washing water for rice husks and the like.

  As described above, the collection device of the above embodiment collects fine particles containing radioactive metal material by foam, collects fine particles containing radioactive metal material by flock, and collects large-sized particles that hardly contain radioactive metal material. The recovery and the recovery of treated water containing almost no radioactive metal material can be performed simultaneously in a single tank, effectively treating turbid water contaminated with fine particles containing radioactive metal material. can do.

  FIGS. 3A to 3C show external photographs of an experimental apparatus manufactured in order to verify that a desired collection process can be performed by the collection apparatus according to the above embodiment. 3a shows a panoramic photo of the experimental apparatus and the first half of the foam recovery process, FIG. 3b shows the second half of the foam recovery process, and FIG. 3c shows the flock recovery process.

This experimental apparatus has, as a basic configuration, a bubble contact cylinder 42, a floc aggregation cylinder 32, a flock collection cylinder 22, a foam collection cylinder 12, a sedimentation cylinder 52, and a fine bubble composed of a nanobubble generator 82 and a microbubble generator 86. As shown in FIG. 3a (1), the flock recovery cylinder and the foam recovery cylinder are formed of continuous cylinders having the same diameter, and the liquid level of the water to be treated is provided. It becomes the boundary. The volume in the tank of this experimental apparatus is 50L, and the water level adjuster of the constant water level tank is set so that the boundary between the flock collection cylinder and the flock collection cylinder is 15 cm from the bottom of the flock collection cylinder.
Using such an experimental device, an experiment was conducted to collect soil particles containing radioactive metal substances from muddy water generated by washing soil particles collected using rice husks and the like in a contaminated field with washing water.

As shown in FIG. 3 a (2), the foam recovery process is such that the surface of the water to be treated is adjusted to 15 cm from the bottom of the flock recovery cylinder before the generation of fine bubbles (a). When generated, the position of the liquid level starts to rise (b). At this time, in the floc aggregation cylinder, bubbles are collected at the tip, and the foam flows toward the upper part of the foam collection cylinder (c).
Then, as shown in FIG. 3b, the foam overflows from the top of the foam recovery cylinder (d-1), and the soil particles entrained in the foam accumulate on the bottom of the foam recovery container 14 (d-2). The soil particles accumulated in the foam collection container and defoamed and concentrated over time can be collected by opening the foam collection valve of the foam collection container (d-3).

  As shown in FIG. 3c, when the fine bubble generating device is stopped, the internal pressure of the pressure tank built in the device is reduced, and the upper air pocket expands at once, as shown in FIG. The expanded volume of water overflows from the foam collection cylinder and the foam is collected (e). When the fine bubble generating device is stopped, the circulation flow in the tank stops, so that the bubbles staying in the tank start to rise all at once, and a floc having a high concentration is formed in the flock collecting cylinder (f). The floc formed in the flock collecting cylinder is stable, and when the flock formation stops, the flock collecting valve of the flock collecting pipe is opened to open the accumulated flock from the lower part of the flock collecting cylinder. (G).

  As described above, the soil particles recovered by using rice husk etc. in the contaminated field by collecting the foam generated by generating fine bubbles and collecting the flock by the recovery processing experiment by this experimental apparatus. It was confirmed that fine particles containing a radioactive metal substance can be recovered from turbid water produced by washing with water.

  In the above embodiment, a single recovery device has been described. However, the recovery device of the above embodiment is provided with a plurality of stages, and the condensed water recovered from the condensed water recovery pipe 34 of the upstream recovery device is collected by the downstream recovery device. You may make it cascade-connect so that it may reprocess as treated water. By comprising in this way, the radioactive metal substance of the treated water collect | recovered can be reduced dramatically and it can also be made to be able to dispose as general waste water.

In the above embodiment, the nanobubble generating device and the microbubble generating device are separately provided as the fine bubble generating means. However, the present invention is not limited to this, and the fine bubble is generated by a single device. You may make it make it.
Further, in the above embodiment, the fine bubble generating device is installed outside the tank, absorbs the water to be treated in the tank, and returns the treated water in which the fine bubbles are generated to the inside of the tank. You may make it install the apparatus which generates a fine bubble in a tank.

  In the above embodiment, in order to suppress the occurrence of swirling flow in the tank, the nanobubble supply pipe and the microbubble supply pipe are installed at positions facing each other on the outer periphery of the bubble contact portion, but the present invention is limited to this. Instead of this, a swirl flow suppressing plate for suppressing swirl flow may be installed in the tank.

  In the said embodiment, although demonstrated as a thing provided with the sediment collection pipe | tube for collect | recovering the sediment in a sedimentation cylinder in the lower part of a sedimentation cylinder, this invention is not limited to this, It settles in a sedimentation cylinder. You may make it collect | recover a deposit directly from the lower part of a sedimentation cylinder.

  In the above embodiment, the treated water supply unit has been described as using a constant water level tank in order to set the water level in the tank at the upper end of the flock recovery cylinder, but the present invention is not limited to this. Instead, for example, a sensor for detecting the water level in the tank may be provided, and the treated water recovery valve may be opened and closed so that the water level is at the upper end of the flock recovery cylinder.

  In the above embodiment, the flock collecting unit is provided with a flock monitoring sensor that monitors the generation state of flocks in the flock collecting cylinder, and when it is detected by the flock monitoring sensor sensor that flocks are accumulated in the flock collecting cylinder, Although it has been described that the floc collecting valve is opened and the floc is collected, the present invention is not limited to this, and the floc collecting valve may be operated by visually confirming the generation state of the floc. .

In the above embodiment, the foaming aid is added to the water to be treated in the tank. However, the foam collecting agent is added to the water to be treated in the tank and the foaming aid is added and supplied to the tank. You may make it provide the foaming aid injection pipe | tube injected into a tank from the upper part of a pipe | tube, and to inject a foaming aid directly.
In the above-described embodiment, the foam recovery unit includes a foam monitoring sensor that monitors the generation status of the foam in the foam recovery cylinder, and when the foam monitoring sensor detects that the generation of the foam is insufficient, the foaming aid Although the description has been made on the assumption that the foaming agent is added by operating the mixer, the present invention is not limited to this, and the foaming aid is added by visually judging the state of foam formation. Also good.
Moreover, in the said embodiment, when the foam generation in the supplied to-be-processed water was not enough, it demonstrated as what adds a foaming aid in a tank, However, This invention is not limited to this, Before supplying the treated water into the tank, a foaming aid may be added to the treated water as necessary.

  In the above-described embodiment, in order to cause aggregation of high-concentration flocs in a short time, it has been described that the operation of the fine bubble generating device is stopped after a lapse of a predetermined time after foam generation, but the present invention is limited to this. However, the fine bubble generator may be operated continuously.

  In the above embodiment, the operation of the water to be treated supply valve, the flock recovery valve, the condensed water recovery valve, the sediment recovery valve, the treated water recovery valve, etc., the fine bubble generator, the vibration generator, the foaming aid mixing device, etc. Although the present invention has been described as including a control device for controlling the operation, the present invention is not limited to this, and the operation of each valve and the operation of each device are performed artificially while visually confirming the situation. Also good.

  In the above embodiment, the recovery device of the present embodiment is provided in a plurality of stages, and the flocculated water recovered from the flocculated water recovery pipe of the preceding recovery device is cascaded so as to be used as the treated water of the subsequent recovery device. However, the treated water collected from the treated water collection pipe of the preceding collection device may be cascade-connected so as to be used as the treated water of the next collection device. This makes it possible to decontaminate the treated water collected from the treated water collection pipe of the last-stage collection device to a level that can be disposed of as general wastewater, with dramatically reduced fine particles containing radioactive metal substances. Become.

Moreover, in the said embodiment, it is equipped with a bubble contact cylinder, a floc aggregation cylinder, a flock collection | recovery cylinder, a foam collection cylinder, a sedimentation cylinder, and a fine bubble generation means, The collection | recovery of the fine particle containing the radioactive metal substance by foam In addition, the collection of fine particles containing radioactive metal material by floc, the collection of large particles containing almost no radioactive metal material, and the recovery of treated water containing almost no radioactive metal material are carried out in a single tank. However, the floc collecting unit may be omitted, and the bubble contact tube, the floc aggregation tube, the foam collecting tube, the settling tube, and the fine bubble generating means may be provided. Even with such a configuration, without using an adsorbent or an aggregating agent, the collection of fine particles containing radioactive metal material by foam, the collection of large particles containing almost no radioactive metal material, and the radioactive metal material It is possible to collect almost all of the treated water in a single tank at the same time, efficiently separate and collect fine particles containing radioactive metal substances from contaminated turbid water, and reduce the amount of radioactive waste. The object of the present invention of reducing can be achieved.
In this case, by collecting the condensed water in the floc aggregation cylinder before collecting the treated water, the fine particles containing the radioactive metal substance in the collected treated water can be sufficiently reduced. As described above, the recovered flocculated water is provided with a plurality of recovery devices, and the flocculated water recovered in the previous stage may be cascade-connected as the post-treatment water, or a single recovery device may be connected. It is also possible to accumulate the collected condensed water and reprocess it as treated water of the same recovery device.

As described above, according to the present invention, without using an adsorbent or a flocculant, fine particles containing radioactive metal substances in muddy water can be efficiently separated and recovered, and the amount of radioactive waste can be reduced. An apparatus and recovery method are provided.
In the above-described embodiment, a case where fine particles containing a radioactive metal substance are collected from turbid water generated by washing soil particles collected using rice husk etc. with washing water in a contaminated field has been described. However, the present invention is not limited to this, and can be applied to the treatment of any turbid water containing fine particles containing radioactive metal substances such as contaminated agricultural water or washed water decontaminated from contaminated soil. .

  Note that the present invention is not limited to the above-described embodiments, and as long as the effects of the present invention are achieved, the constituent elements described in the respective embodiments are appropriately replaced, new constituent elements are added, or a part thereof It goes without saying that the constituent elements may be deleted.

DESCRIPTION OF SYMBOLS 10 Foam collection | recovery part 12 Foam collection | recovery pipe | tube 14 Foam collection | recovery container 16 Foam monitoring sensor 20 Flock collection | recovery part 22 Flock collection | recovery cylinder 24 Flock collection | recovery pipe | tube 25 Flock discharge valve 26 Flock monitoring sensor 30 Flock flocculation part 32 Flock aggregation pipe | tube 34 Aggregated water collection pipe | tube 35 Condensed water discharge valve 40 Bubble contact part 42 Bubble contact cylinder 50 Sedimentation part 52 Sedimentation cylinder 54 Vibration generator 56 Treated water recovery pipe 57 Treated water recovery valve 60 Sediment recovery part 62 Sediment recovery cylinder 64 Sediment recovery valve 66 Sediment Discharge valve 70 To-be-treated water supply part 72 Constant water level tank 74 Contaminated washing water introduction pipe 75 Water level regulator 76 To-be-treated water supply pipe 77 To-be-treated water supply valve 80 Fine bubble generating part 82 Nano bubble generating device 83 Nano bubble water absorption pipe 84 Nano bubble Supply pipe 86 Micro bubble generator 87 Water absorption for micro bubble 88 microbubble supply pipe 90 blowing grant agent added 92 blowing grant agent mixer 93 foam Grant for water tube 94 blowing grant agent supply pipe 100 controller

Claims (16)

A device that collects fine particles containing radioactive metal from contaminated turbid water without using adsorbents or flocculants,
A bubble contact cylinder for bringing fine bubbles into contact with the treated water to be supplied, and attaching fine particles containing the radioactive metal substance to the fine bubbles to float;
A floc aggregation cylinder formed in a reverse funnel shape, connected to the upper part of the bubble contact cylinder, and agglomerates fine particles containing radioactive metal substances that adhere to and float on the fine bubbles as flocs;
Connected to the upper part of the floc aggregation cylinder and connected to the lower part of the floc collection cylinder for accumulating and collecting the floc aggregated by the floc aggregation cylinder, and accumulated in the floc collection cylinder A flock collecting section having a flock discharge pipe for discharging the flock;
A foam recovery cylinder connected to an upper part of the flock recovery cylinder and recovering fine particles containing a radioactive metal substance that floats by adhering to the fine bubbles by a foam generated on the liquid surface, and overflowed from the foam recovery cylinder A foam recovery unit having a foam recovery container for containing the foam;
A funnel-shaped, connected to the lower part of the bubble contact cylinder, settles large-diameter particles contained in the supplied water to be treated, and collects from the lower part as a sediment,
A treated water supply pipe for supplying treated water into a tank formed by the bubble contact tube, the floc aggregation tube, the sedimentation tube, and the flock collection tube;
Fine bubble generating means for generating the fine bubbles in the water to be treated in the tank;
A treated water recovery pipe for recovering the treated water from the tank;
Supply of water to be treated into the tank by the treated water supply pipe, generation of fine bubbles by the fine bubble generating means, recovery of flocs from the flock recovery pipe, and sediment from the lower part of the settling cylinder And control means for controlling at least a part of the recovery of the treated water in the tank from the treated water recovery pipe,
With
Collection of fine particles containing radioactive metal material by foam, collection of fine particles containing radioactive metal material by floc, collection of large-sized particles containing almost no radioactive metal material, and processing containing almost no radioactive metal material A fine particle recovery apparatus containing a radioactive metal substance in muddy water, characterized in that the recovery of water can be performed simultaneously in the treatment in a single tank.   A tank for storing the water to be treated supplied into the tank, and a constant water level tank having a water level adjusting means for adjusting the water level of the water to be treated in the tank so as to coincide with the upper end of the flock collecting cylinder, The fine particle recovery apparatus containing a radioactive metal substance in muddy water according to claim 1, wherein the apparatus is provided on the upstream side of the treated water supply pipe.   In the lower part of the sedimentation cylinder, a sediment recovery cylinder that takes in the sediment precipitated in the sedimentation cylinder and accumulates a certain amount thereof, a sediment recovery valve that takes the sediment in the sedimentation cylinder into the sediment recovery cylinder, and The radioactive metal substance in muddy water according to claim 1 or 2, further comprising a sediment recovery unit having a sediment discharge valve for discharging the sediment accumulated in the sediment recovery cylinder to the outside. Contains fine particle recovery equipment. The settling cylinder includes vibration generating means for applying vibration to the settling cylinder in order to remove deposits attached to the inner surface of the settling cylinder.
The control means has a function of closing the sediment discharge valve, opening the sediment recovery valve, and controlling the vibration generating means to operate for a predetermined time.
The fine particle collection | recovery apparatus containing the radioactive metal substance in muddy water of Claim 3 characterized by the above-mentioned.   The fine bubble generating means generates micro bubbles in the water to be treated in the tank and supplies the micro bubbles to the tank, and generates nano bubbles in the water to be treated in the tank to generate the micro bubbles in the tank. The fine particle collection | recovery apparatus containing the radioactive metal substance in the muddy water in any one of Claims 1-4 provided with the nano bubble generation | occurrence | production means to supply.   The microbubble supply pipe for supplying the microbubbles generated by the microbubble generating means into the tank, and the nanobubble supply pipe for supplying the nanobubbles generated by the nanobubble generating means into the tank are the bubble contact cylinder. 6. The fine structure containing radioactive metal material in turbid water according to claim 5, wherein the fine metal composition is provided at a position opposite to the outer periphery of the turbid water and configured to suppress generation of a swirling flow in the bubble contact tube. Particle recovery device.   The radioactive metal substance in muddy water according to any one of claims 1 to 5, wherein the bubble contact cylinder includes a swirl flow suppressing plate that suppresses the generation of swirl flow in the bubble contact cylinder. Contains fine particle recovery equipment. The flock collecting unit includes a flock monitoring sensor that monitors a generation state of flock accumulated in the flock collecting cylinder,
The control means is configured to collect the flock accumulated in the flock collecting cylinder from the flock collecting pipe when the flock generation state monitoring sensor detects that the flock is accumulated in the flock collecting cylinder. Have the ability to control,
The fine particle collection | recovery apparatus containing the radioactive metal substance in muddy water of any one of Claims 1-7 characterized by the above-mentioned. A foaming assistant supplying means for supplying a foaming assistant for supporting the generation of foam for the water to be treated supplied into the tank,
The foam recovery unit includes a foam monitoring sensor for monitoring the generation state of foam,
The control means has a function of operating the foaming aid supplying means when the generation of a predetermined foam is not detected by the foam monitoring sensor after a predetermined time has elapsed since the fine bubble generating means was operated.
The fine particle collection | recovery apparatus containing the radioactive metal substance in muddy water of any one of Claims 1-8 characterized by the above-mentioned.   The control unit has a function of controlling the fine bubble generating unit to stop after operating for a predetermined time and to collect flocs with high concentration generated after the stop. The fine particle collection | recovery apparatus containing the radioactive metal substance in muddy water in any one of. The lower part of the said floc aggregation cylinder of the fine particle collection | recovery apparatus provided with multiple stages of the fine particle collection apparatus containing the radioactive metal substance in the muddy water in any one of Claims 1-10, and containing the radioactive metal substance in the muddy water of each stage Includes a flocculated water recovery pipe for recovering the treated water of the floc flocculation cylinder after the flocc recovery by the floc recovery section is completed as flocculated water,
The agglomerated water collected from the aggregated water recovery pipe of the fine particle recovery device containing the radioactive metal substance in the preceding muddy water is supplied as treated water of the fine particle recovery device containing the radioactive metal substance in the subsequent muddy water. A fine particle collection device containing radioactive metal substances in muddy water cascaded to each other. A bubble contact cylinder for bringing fine bubbles into contact with the treated water to be supplied, and attaching fine particles containing the radioactive metal substance to the fine bubbles to float;
A floc aggregation cylinder formed in a reverse funnel shape, connected to the upper part of the bubble contact cylinder, and agglomerates fine particles containing radioactive metal substances that adhere to and float on the fine bubbles as flocs;
Connected to the upper part of the floc aggregation cylinder and connected to the lower part of the floc collection cylinder for accumulating and collecting the floc aggregated by the floc aggregation cylinder, and accumulated in the floc collection cylinder A flock collecting section having a flock discharge pipe for discharging the flock;
A foam recovery cylinder connected to an upper part of the flock recovery cylinder and recovering fine particles containing a radioactive metal substance that floats by adhering to the fine bubbles by a foam generated on the liquid surface, and overflowed from the foam recovery cylinder A foam recovery unit having a foam recovery container for containing the foam;
A funnel-shaped, connected to the lower part of the bubble contact cylinder, settles large-diameter particles contained in the supplied water to be treated, and collects from the lower part as a sediment,
A treated water supply pipe for supplying treated water into a tank formed by the bubble contact tube, the floc aggregation tube, the sedimentation tube, and the flock collection tube;
Fine bubble generating means for generating the fine bubbles in the water to be treated in the tank;
A treated water recovery pipe for recovering the treated water from the tank;
A method for recovering fine soil particles containing radioactive metal material from contaminated turbid water without using an adsorbent or a flocculant using a fine particle recovery device containing radioactive metal material in turbid water comprising:
Supplying the treated water into the tank from the treated water supply pipe, and setting the water level of the treated water in the tank at the upper end of the flock collecting cylinder;
Activating the fine bubble generating means to generate fine bubbles in the bubble contact tube;
A step of recovering the floc accumulated in the flock collecting cylinder from the flock collecting pipe when it is confirmed that the flock is accumulated in the flock collecting cylinder;
Collecting the foam when the foam accumulated in the foam collection container reaches a predetermined amount;
Recovering the sediment precipitated in the sedimentation cylinder from the bottom of the sedimentation cylinder;
A step of recovering treated water in the tank after the recovery of the floc by the step of recovering the floc and the recovery of the precipitate by the step of recovering the precipitate are completed;
With
Collection of fine particles containing radioactive metal material by flock, collection of fine particles containing radioactive metal material by foam, collection of large-sized particles containing almost no radioactive metal material, and processing containing almost no radioactive metal material A method for recovering fine particles containing a radioactive metal substance in muddy water, wherein the recovery of water can be performed simultaneously in the treatment in a single tank. Supplying washed contaminated water obtained by washing rice husks and the like, to which soil particles are adhered in a contaminated field with wash water, as the treated water;
Reusing the treated water recovered by the step of recovering the treated water in the tank as washing water for washing the rice husks, etc .;
The method for recovering fine particles containing a radioactive metal substance in muddy water according to claim 12, comprising:   When the generation of the predetermined foam is not confirmed in the foam recovery unit after a predetermined time has elapsed since the operation of the microbubble generation means in the step of generating the microbubble, a foam generation assistant is introduced into the tank. The method for recovering fine particles containing a radioactive metal substance in muddy water according to claim 12 or 13, further comprising a step. The step of generating the fine bubbles is stopped after operating the fine bubble generating means for a predetermined time,
The radioactive metal in muddy water according to any one of claims 12 to 14, wherein the step of collecting the floc collects a floc having a high concentration generated after the fine bubble generating means is stopped. A method for collecting fine particles containing a substance. A plurality of fine particle collection devices containing radioactive metal substances in the muddy water are provided in a plurality of stages, and a flock by the flock collection unit is disposed below the floc aggregation cylinder of the fine particle collection device containing the radioactive metal substances in muddy water in each stage. The radioactive metal substance in muddy water is contained using the fine particle recovery device containing the radioactive metal substance in muddy water equipped with a condensed water recovery tube that collects the treated water of the floc aggregation tube after the collection is completed as agglomerated water. A method of collecting fine particles,
Supplying the aggregated water recovered from the aggregated water recovery pipe of the fine particle recovery apparatus including the radioactive metal substance in the turbid water in the first stage as the treated water of the fine particle recovery apparatus including the radioactive metal substance in the subsequent turbid water; A method for recovering fine particles containing a radioactive metal substance in turbid water according to any one of claims 12 to 15, characterized by comprising: